PREDATOR CONTROL AND ERADICATION

Pacific Rim Conservation conducts and manages several predator control projects in Hawaii, and has successfully conducted several predator eradications in Hawaii both on offshore islets and from within fenced areas. On most islands throughout the Pacific region, alien terrestrial mammals (rodents, mongoose, mustelids, cats, dogs, and ungulates) pose a serious threat to native biota that did not evolve with mammalian predators and lack natural defenses against these animals. We work with State and Federal agencies and other pest control organizations to ensure that animal welfare guidelines are followed and that the most current, effective, and humane techniques are employed. Methods include live trapping, snap trapping, and poison bait stations. Our staff are certified restricted pesticide applicators.

Left – rat at dummy elepaio nest. Right – rat bait station

Nihoku predator-proof fence multi-species eradication

We designed and implemented a successful three-species (cat, rat and mouse) predator removal operation from inside the predator proof fence at Kilauea Point National Wildlife Refuge using a combination of secure bait boxes and traps. We also developed and implemented the pre and post monitoring protocols of both pest and native species to determine their response to the removal of predation pressure. For complete partner information, go to www.nihoku.org.

Kaena Point predator-proof fence multi-species eradication

With funding from the David and Lucille Packard Foundation and in partnership with the Hawaii Department of Land and Natural Resources, we designed and implemented a successful five-species predator removal operation from inside the predator proof fence at Kaena Point Natural Area Reserve using a combination of secure bait boxes and traps. Previous predation rates in the reserve resulted in up to 15% of the fledgling seabirds killed every year, as well as preventing several endangered plant species from reproducing. Post- eradication monitoring revealed that the average Wedge-tailed Shearwater nesting success increased from 28% to 54%, and the number of chicks fledging each year increased by 384%. Read more: Report #83, Report #86, and Report #89

Rat eradication from Mokuauia Islet

In collaboration with the Hawaii Department of Land and Natural Resources, we successfully removed black rats from Mokuauia Island using a combination of bait boxes and snap traps. Mokuauia (also called Goat Island) is a 13-acre State Seabird Sanctuary on the northeastern coast of Oahu in Laie Bay and is 16 native plant species, an estimated 6,500 nesting Wedge-tailed Shearwaters and several migrant shorebirds, including the rare Bristle-thighed curlew. Outcomes of this project can be downloaded here.

Predator control to protect the Oahu Elepaio

For 20 years, we have conducted control of alien rodents to reduce nest predation and improve survival of Oahu Elepaio, and monitoring efficacy of the rodent control program, in collaboration with the Hawaii Division of Forestry and Wildlife, the U.S. Army, and the Nature Conservancy of Hawaii. When rats are trapped, twice as many Elepaio pairs successfully raise a chick and fewer females are eaten. For more information on this project and on the Oahu Elepaio, visit www.elepaio.org. For published results of this work, see Report #22

Predator control to protect Red-tailed Tropicbirds

For 11 years, we have conducted control of alien rodents and mongoose to reduce nest predation and improve survival of a small Red-tailed Tropicbird colony on Oahu, and monitoring efficacy of the control program. Results have been highly positive with both the reproductive success and colony growth rate increasing as a result of the work. For published results of this work, see Report #95.